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 A104145 a(1) = 1; let A(k) = sequence of first 2^(k-1) terms; then A(k+1) is concatenation of A(k) and (A(k)-1) if a(k) is odd, or concatenation of A(k) and (A(k)+1) if a(k) is even. 1
 1, 0, 2, 1, 2, 1, 3, 2, 0, -1, 1, 0, 1, 0, 2, 1, 2, 1, 3, 2, 3, 2, 4, 3, 1, 0, 2, 1, 2, 1, 3, 2, 0, -1, 1, 0, 1, 0, 2, 1, -1, -2, 0, -1, 0, -1, 1, 0, 1, 0, 2, 1, 2, 1, 3, 2, 0, -1, 1, 0, 1, 0, 2, 1, 0, -1, 1, 0, 1, 0, 2, 1, -1, -2, 0, -1, 0, -1, 1, 0, 1, 0, 2, 1, 2, 1, 3, 2, 0, -1, 1, 0, 1, 0, 2, 1, -1, -2, 0, -1, 0, -1, 1, 0, -2, -3, -1, -2, -1, -2, 0, -1, 0, -1, 1 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 LINKS FORMULA a(n) = 1 - A137412(n). - Leroy Quet, Apr 22 2008 EXAMPLE a(3) = 2 is even, so A(4) (1,0,2,1,2,1,3,2), the first 8 terms of the sequence, is A(3) (1,0,2,1) concatenated with each term of A(3) plus one (2,1,3,2). CROSSREFS Cf. A137412. Sequence in context: A134780 A247379 A154819 * A230981 A123675 A322872 Adjacent sequences:  A104142 A104143 A104144 * A104146 A104147 A104148 KEYWORD easy,sign AUTHOR Leroy Quet, Mar 07 2005 EXTENSIONS More terms from Joshua Zucker, May 10 2006 STATUS approved

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Last modified December 5 11:05 EST 2021. Contains 349557 sequences. (Running on oeis4.)